cm:Level2TextBlock: us-gaap:PlantConstructionUsingIntermediaryPolicy
| Plant Construction Using Intermediary, Policy [Policy Text Block] |
| us-gaap:PlantConstructionUsingIntermediaryPolicy |
| Disclosure of accounting policy for a utility company's accounting treatment when it uses an intermediary for plant construction. The intermediary's work in progress is included by the utility in an appropriate caption under the utility plant. The related debt is included in long term liabilities and disclosed on the balance sheet or in a note. |
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| us-gaap:PlantConstructionUsingIntermediaryPolicy |